Moses smith salteb



M. S. SA-LTER.

Furnace for IVJalking Wrought Iron.

Patented Nov. 20, 1849.

A ll-ll N. PETERS. Phuloliflwgraphcr. Wnhi nnnnnn a UNITED STATES PATENT4 FFICEQ MOSES SMITH SALTER, OF NEWARK, NEV JERSEY, ASSIGNOR TO SALTER,NORTON & POINIER.

PROCESS FOR MAKING MALLEABLE IRON DlRECT FROM THEORE.

Specification forming part of Letters Patent No. 6,6, dated November 20,1849.

T0 aZZ whom it may concern:

Be it known that I, Mosns SMITH SALTER, of Newark, Essex county, in theState of New Jersey, have invented a new and useful furnace for makingwrought-iron of a superior quality directly from the ore in a singleprocess and by means of anthracite or other fossil coal or charcoal; andI do hereby declare that the following is a full, clear, and exactdescription of the construction and operation of the same, referencebeing had to the annexed drawings, making a part of this specification.

The furnace is constructed of masonry with suitable bracings, and linedin the interior, either in whole or in part, with wrought-iron,fire-brick, or other material least affected by heat. It is shaped in asquare or oblong square, or round, or oval, or other most convenientform. It is divided into three compartments or chambers, situated oneabove another.

Figure 1 is a cross-section. Fig. 2 is a side elevation. Fig. 34's anend elevation. Fig. 4: is the upper chamber. Fig. 5 is a longitudinalsection. Fig. 6 is the top of the furnace. Fig. 7 is the middle chamber.Fig. Sis the lower chamber. Fig. 9 is the foundation-walls.

The numbers for reference are the same for the same objects on thedifferent figures.

The fire place or grate for fuel, No. 10, is within the furnace, and atone end of the lower compartment or chamber, Fig. 8, from which chamherit is partly separated by a wall or two parallel walls, No. 11, raisedtoa convenient height, and over which walls a space is allowed for thepassage of the draft. The draft passes horizontally on in areverberatory manner along the entire length of the lower chamber, A,Fig. 5; in the roof of which, at the opposite end, there is an opening,No. 12, for its passage up into the middle chamber. It passes in thesame manner through the middle chamber, B, Fig. 5, to the oppositeend,where there is an opening, No. 13, for its passage up into the upperchamber, 0, Fig. 5. It passes again in the same manner through the upperchamber to the opposite end, where it finally escapes by a chimney, No.14. The ores,with the necessary materials for their reduction, are

introduced into the upper chamber through,

an opening, No. 15, in the roof. Over this opening they are firstsuspended in a hoppershaped receptacle, No. 16, which receptacle isprovided with a shutter below, No. 1.7, corresponding with the openingin the roof. The ores are then at suitable intervals of time re moved tothe opening for the draft, through which they are thrown down to themiddle chamber. Next they are removed to the opposite end of the middlechamber, where they are thrown down through the opening for the draft tothe lower chamber. Next they are removed in the lower chamber to thefinishing-basin, No. 18, near the fire, where the ef fects of the heatare completed, and whence they are taken out in the metallic state,ready to be finished by hammering or otherwise. Through the sides of allthe chambers openings No. 19 are made, through which the ores and theaccompanying materials for their reduction may be frequently agitated bysuitable instruments, and moved along from one end of the severalchambers to the other, and finally through which (No. 20) the metal maybe molded and taken out from the furnace. There is another opening, No.21, opposite the space between the two walls which separate in part thefire-place from the first chamber. The said space No, 22 may be used forreheating the iron. It may also be omitted as not essential, and oneseparating-wall may be constructed instead of two. There are alsoopenings for the blast, No. 23, for the fuel, No. 24; for the removal ofashes, No. 25, and for the letting off, No. 26, of any liquid matterswhich may accumulate in the finishingfurnace. Through the floor of thelower chamber there is an opening, No. 27, in the end opposite the fire,through which may fall the cinders and ashes and other solid materialscarried along thither by the draft. For the same purpose other suitablereceptacles are provided in the other chambers.

To prevent an undue accumulation of heat in the middle and upperchambers, or to prevent the introduction into said chambers of cold air,or air charged with oxygen, coming through openings in the lowerchamber, flues No. 28 are made to lead from the lower chamber upwarddirectly through the top of the furnace. These fines are ordinarily keptclosed by dampers No. 29'on their tops, and when l purposeofthethreeseveral chambers, of which they are opened the draft isprevented from pursuing its ordinary passage by a suitable damper, No.30, metallic or otherwise, closing the top of the chimney. Further, toprevent the too violent effects of the heat, openings No. 33 are made inthe sides and ends of the furnace for the introduction of cold airbetween the roof of the lower chamber and the floor of the middlechamber, and also between the roof of the middle chamber and the floorof the upper chamber. The spaces between the roof of one chamber and thefloor of the succeeding chamber above may be greater or less atconvenience. Levers No. 31, with cords, chains, or rods attached, aremounted on the top of the furnace for working the shutters in the usualmanner. The floors No. 82 of the several chambers may be eitherhorizontal or inclined. The lower chamber is raised up from the groundfor the convenience of working, for the easy flowing away of liquidimpurities, and for the falling down of ashes and cinders.

The construction of my furnace as above specified affords the followingadvantages:

gether, and all the ores and their accompanying materials become in turnequally exposed to the heat and to the draft; third, the opportunity forthe ores and their accompanying materials to fall down from chamber tochamber, this being attended with all the several advantages enumeratedas attending agitation, with this addition, that these advantages arevaried and modified somewhat differently in falling down, and arerendered more complete, at the same time that they retain their elevatedtemperature. The draft is unconfined and moves freely and rapidly forcarrying off the impurities. The atmospheric air is deprived for themost part of its free oxygen by the fuel of the fire-place, andtherefore, while passing rapidly through the ores, it does not oxidizethe metal, and does not consume the carbon, which is consequentlyallowed freely to exthe upper is the heating and vaporizing, the middlethe mixing, and the lower the reducing and finishing chamber.

The ores can be reduced to metals of more than ordinary purity by theabove-rnentioned means provided for the escape of their impurities. The.ores of iron may be reduced to wrought or malleable iron without firstcar bonizing the iron. The ores of iron may be reduced also to acarbonized state, either as steel or as cast orpig iron. This may bedone by having less agitation and adding an excess of carbon.

The necessary materials for the reduction of the ores may be introducedat different temperatures and at different stages of reduction,according as their presence may be needed, For example, when lime isrequired for separating silica from iron ore, such lime need not beintroduced at the beginning of the process, when the temperature is low,for at such temperature it cannot act upon the silica, and its presencewould certainly interfere with the free expulsion of other impurities.It may, therefore, be introduced partly in the middle and partly in thelower chamber as it may take due effect, and in quantities as it may beneeded. The carbonic-acid gas evolved from the limestone or shellsintroduced in the lower chamber tends to protect the carbon and ores andimpurities from the residuum of free oxygen left in the draft.

Another great advantage from the use of my furnace is that it yields agreater percentage of metal from any given amount of ore than isobtained by other furnaces heretofore used, the ores and the necessarymaterials for their reduction being through the whole process completelyunder control, subject to such various treatment as they may require atdif ferent stages of reduction, and opportunities being afforded for theescape of impurities without their combining with and carrying off themetals.

One of the great advantages for the reduc= tion of iron ores by myfurnace is this, that it will reduce such ores by the use of anthracitecoal alone, both as fuel and as the deoxidizing agent on the ores. Theimpurities of that coalsuch as sulphur'-are expelled at a lowtemperature before such coal acts on the ore, and consequently beforethe metals still in the ore can be effected by such impurities.

Another important advantage is the saving of coal to a large amount,both as a fuel and as a deoxidizing agent. This is effected as adeoxidizing agent because no more coal is used than is necessary toextract the oxygen from the ores, none' entering into the iron, and alsofrom the rapidity of the operation, very little being carried off by thedraft.

The saving of coal as fuel is effected partly by the various facilitiesalready enumerated for the expulsion of impurities, partly by theprevention of the escape of heat, one chamber being compacted uponanother, and partly by the long continuous range of the draft, to thewhole force of which the ores are exposed by their position, agitation,and falling.

By the freedom of draft in my furnace there is no mechanical .pressureby said draft upon the ores. Therefore it cannot by the force of suchpressure prevent the chemical decomposition of the ores, nor carry awaythe pulverized particles of ores and carbon.

I am aware that ores are roasted in kilns and furnaces separate from thefurnaces in which they are afterward fluxed and reduced, and also thatin forgefires and similar ironworks the flux isaddedintheordinaryworkinghearth, where it is necessarily heated at considerableexpense of time and fuel, and, finally, that in high-blast furnaces theflux is simply mixed with the ore, usually in separate charges, and thatunder this treatment the ore and flux are often very imperfectly mixedand incorporated; and it is to overcome these different imperfections ofthe ordinary processes of making iron that my plan of operations hasbeen devised. I flux my ore by working in a separate and appropriatechamber.

\Vhat I claim as my invention, and desire to secure by Letters Patent,is-

The process of manufacturing iron directly from the ore in a furnacecomposed of three combined chambers one above another, all actuated bythe same fire,whereof the upper chamber is used for heating anddeoxidizing, the middle chamber for fluxing and working, and the lowerchamber for reducing and finishing the iron, substantially in the mannerand for the purposes herein set forth.

M. SMITH SALTER. \Vitnesses:

A. S. HAMLIN, WM. WILLIAMs.

